A lot of people get surprised when the security plus covers the concept of wireless access points because
whaps while they certainly do have some security issues we tend to not zero in on just the wireless
access points when we're talking about that.
And unfortunately that's a mistake because there's a lot of issues particularly with your wireless signal
that's getting out that are real security issues.
So let's make sure we understand a couple of things before we get into deep.
Now the most important thing I want to start off with is the idea of think enterprise.
Now what I've got here in front of me is a good old home wireless access point but it's actually a lot
more than a wireless access point.
If you take a look at this guy you'll see he's actually a built in router.
You see these in people's homes and in small offices all the time.
They're great little boxes but when we're talking about real security we move into a whole other world.
So what I have here is some wireless access points that are a little bit more serious when it comes
to dealing with enterprises.
First one I want to talk about is this beastie.
So this beastie is a wireless access point.
This is a way not to steal the Cisco wireless access point it's actually just been retired here total
seminars.
Now this is what we call a thick client.
This is a standalone wireless access point.
When you take a look at a beast like that what you're talking about is a device that we have to configure
by itself so if I've got three of these up there I've got to go into each one they all have web interfaces.
I'm going to go to each one of these guys.
I'm going to do whatever configuration I need to do and that is a great example of a standalone or a
fat client.
Sometimes you hear the term thick client as well.
What's a little bit more common today in the enterprise environment is something like this.
So what this is is a wireless access point.
It's a lot smaller this type of wireless access point is very different from that big thick client.
This is what we're going to call a thin client.
You don't go into this guy and configure him through a web page.
This guy has to be handled through a controller so it's controller based.
These are actually very very convenient because what I can do a lot of times if I'm setting up a wireless
network for office I'm going to be using the same SS ID.
I'm going to be bouncing around different channels so each wireless access point has got a good Cris
signal and I want to configure all these guys we call them hockey pucks you hear that term quite a bit.
And I want to configure them all at once.
So what we'll do.
Like here told the seminars There's a company called Ubiquiti love you Ubiquiti that has a wonderful
powerful tool I buy a number of these hockey pucks.
I place them properly and then I plug them in to a switch and through one control or one piece of software
I set them all up simultaneously.
When you've got a lot of wireless access points the hassle of going through a whole bunch of thick clients
versus just one little thin client controller is much much better.
OK.
So whether you have a fat client a thick client or a thin client a hockey puck you have to deal with
the issue of antennas.
Now if you'll notice pretty much all of these devices have built in antennas ready to go.
And for most of us these antennas are absolutely fine.
This guy here doesn't look like it but he's actually gotten intended to.
However if you need too many of these wireless access points have the ability to take an external antenna
like this little guy I've got right here.
Put that up there so you guys can look at it.
The idea behind external antennas is that sometimes the built in antennas that come with a wireless
access point don't provide enough signal and signal strength is a big deal with these when we're talking
about signal strength.
We use the term decibels or D-B.
So I don't want to get into a big deciples discussion because all you radio guys are going to jump out
of your videos and beat me up because I'm not a radio guy.
The bottom line is when we're talking about BVI what we're talking about is think about like a boost.
How good of a signal does this device have without that antenna or with a built in antenna versus me
adding a stronger antenna.
So in general a larger decibel value is better.
And that's really important for the exam.
OK so next thing I want to talk about are the different physical antenna types.
There's a lot of I mean they all just look like little sticks right.
Well there's actually a lot more to it than that.
It has to do with how the signal is presented so let's go through the basic and genotypes First of all
we have what's called an omni or an omni directional
an omni directional basically looks like a big basketball.
So the signal goes in every possible direction.
You'll see these used out of doors in very very large like in a basketball court or something like that
because everybody no matter which directions point he needs a signal.
Secondly we have what's called a dipole.
Now this little these little entities here are actually dipoles.
When we say a dipole actually has two little antennas built in this it looks like one antenna.
But there's really two.
A dipole makes basically take a bagel and then stomp on it.
And that's what a dipole signal is dipoles have some real big benefits.
Number one they're really good if you're just trying to shoot around a single floor or if you're just
trying to hit a single level or a deck in a ship or something like that.
The other nice thing about dipoles if look right here you'll see these dipoles always are bendy like
this.
And the reason they do that is because a lot of times especially with something like this by little
adjustments I could hit maybe of not only the floor I'm on but maybe a second floor as well.
So that's why dipoles are extremely common next are what we call directionals now a directional shoots
out a really long beam so think about like a lighthouse and how a lighthouse shoots out a really long
individual beam.
There are two different types of directionals that we'll see first is going to be what we call a yagi
yagis look like the antennas used to see on tops of people houses and they're designed to pick up and
send a very very pointed signal.
Now if you really want to go crazy about it then we can add what are called pair of bollix.
So they look like little radar dishes and these things are usually even more powerful than yagis in
general and they're designed for very very long distances.
There's some really interesting competitions where using these types of antennas they want to see who
can shoot the furtherest 10:42 distance.
Now they're in the hundreds of miles and they have to shoot from mountaintop to mountaintop.
Yeah they're pretty nerdy.
OK.
There is one more type of antenna that kind of directional and kind of omni and that's called a patch
a patch is half of an omni.
So what we're looking at is take that sphere and basically cut it in half.
You can even have dipole type patches that will shoot basically half a dipole.
The idea behind these is that these are great.
In fact this guy right here is a patch antenna I can bolt him onto a wall in a office and it'll shoot
out a big signal in one direction and virtually no signal at all at the other direction.
So if I've got an exterior wall and I know what people in the parking lot trying to get into my wireless
network patches are extremely common.
OK.
The idea behind antennas like this is that you have to place them.
So the questions that you're going to see in the security plus are actually pretty trivial.
So if you're doing something in a big basketball stadium you'd probably use an omni If you're outdoors
you're probably going to be using some form of dipole if you're going to be placing things against walls.
Look for a patch.
And if you ever have to shoot long distances in particular between buildings and such.
You're always going to be using some form of directional either a yagi or a parabolic.
Also keep in mind that with yagis anything that's directional they actually have to be pointed to each
other.
So don't be surprised if somebody says oh point that to the left or point that to the right so you're
always thinking in terms of direction.
All right.
Now with a good understanding of antennas we've got a good start in terms of our security good antenna
placement controls the signal and make sure that we're not putting it in places where naughty people
can and that's the most important thing to remember what we're talking about the different types of
antennas.
Now I want to stop for a minute and talk about something that's completely different still and wireless.
Let's take a moment and talk about band selection.
The ATO 2:11 standard has two different bands the 2.4 gigahertz band and the five gigahertz band.
Now when we're talking about the bands you're going to use it really boils down to the technology that
you want and the relative speeds that you want and how crowded things are.
So what I'm using is a Wi-Fi analyzer built into my phone right here and I'd like to start by just taking
a look on this phone and look how crowded everything is.
This is a mess of the 2.4 gigahertz band now 2.4 gigahertz is fine for older 10:52 technologies.
But the real excitement is when you watch it as I switch over as we go into the five gigahertz band
now in this case the 5 gigahertz band isn't nearly as crowded and especially with technologies like
10:52 a c you're pretty much going to want to go to the five gigahertz band every now and then you'll
see somebody supporting 2.4 and that's if somebody comes in with a really old laptop or something like
that.
So five gigahertz band is where it's at.
The challenge with the five gigahertz band is how do you deal with your channel with now with 2.4 gigahertz.
You have very specific channels and on wireless access points you can often set that channel very calm
today with the more common standards in the five gigahertz band.
It's rare to run into wireless access points that allow you to manually configure the channel and there's
a good reason for that.
A wireless access point today has auto sensing features and if it's senses that a particular channel
is really really crowded it's just going to go ahead go someplace else.
And we like that feature so automated channels on five gigahertz is common.
However there's something else that is not common and that is channel with now.
When you take a look at the different types of channels in the five gigahertz band you have 10 megahertz
wide 20 maigre it's wide 40 big or it's wide and ginge and in general the wider the channel the better
the throughput you're gonna get it specially when you're using more advanced technologies like memo
with ATo 2:11 a c.
The downside is and let's take a look at the screen one more time is that if you take a look here you
can see where it says total Wi-Fi studio.
Look how wide that channel is.
We've done that on purpose because when I originally set this up there wasn't anybody else in here and
I had this amazing throughput.
So and as I'm watching this I realize that I'm going to have to go into my wireless access points and
narrow that channel with so that they can find an easier place to auto hop into that isn't quite so
terribly crowded.
So that's what we need to cover for the security plus on wireless access points for me.
Number one I'm always going to prefer a thin controller based client over a fat client especially if
I have two or more wireless access points.
I'm going to take a lot of time not only selecting my antennas but also making sure that the antenna
placement supports just my users and nobody else.
And third I'm going to take the time with my band selection and my channel with to make sure that I've
got the best possible signal I can get.